I'm using an incredible amount - probably around 400 objects (mostly instances of the same objects) or so per layout, maybe 20 on-screen at a time. I have read the performance tips and followed them very closly. This is unfortunately a webgl/canvas2d flaw more than coding or game design.
And yes, for an object or two I am using sine.
I'll be releasing the demo shortly.
This still doesn't explain why I'm having this issue with webfonts.